Now I've seen it closer it doesn't look bad and I wondered if this was common with carbon forks? I guess it's where the crown meets the carbon leg?

not too bad, it'll put more than a hairline fracture in your face when it goes (soon)

common, not statisticaly out of all the carbon/alloy forks on the market not many will have failed, but of those that do that's not an uncommon of place for them to go where the two parts are bonded together.

There is a good chance that bike uses specialized mindset headset which is unique and and come in two versions crappy cage bearing and sealed bearing.
You will need to reuse the crown race , as with all forks it will come off given the right force / tool